The present invention relates to an alarm system for containers such as attache cases.
Alarm systems for attache cases and the like have been known wherein the alarm is set to be activated when the attache case is snatched from the carrier's hand. Generally this is accomplished by attaching a manually operable switch to the handle of the attache case, which upon its release, triggers the alarm. The alarm system is so designed that it generates a monotone acoustic signal and may also generate intensive smoke and/or fog by means of built in petards. Basically, however, the known systems do not have the ability to monitor the attache case in a rest position wherein the case is set down and not transported and to monitor the condition during the transport so that when its position is changed, it gives an alarm.
The only safety state which is monitored in the prior art systems is respectively that of carrying the attache case by an authorized person or that of the case being in erect position and only deviation from the respective single safety state is evaluated for triggering the alarm. Other safety states for the attache case cannot be constituted selectably as the safety state to be monitored.
It is an object of the present invention to provide a system wherein it is possible to differentiate between at least two states or conditions for the attache case by which deviation from either of the conditions beyond a load safety factor would trigger the alarm. In accordance with the system of the present invention, it is possible to secure an attache case in safe condition practically in any position, and in active state against unauthorized contact, removal, or arrestation.
It is a further object of the present invention to provide an alarm system having an acoustic alarm signal unlike those presently known so as to be clearly distinguishable from surrounding environmental noises and having a level modulated in an undulating siren manner.